Chemical signals released by an organism that trigger a behavioural or physiological response in another member of the same species. In insects, pheromones are well-documented and drive mating, alarm, and trail-marking behaviours. In humans, the existence and function of pheromones remains scientifically contested. The perfume industry has marketed 'pheromone perfumes' extensively, but peer-reviewed evidence for their efficacy in humans is thin.
Pheromones are not an olfactory category. Androstenone, the most commonly cited human 'pheromone,' smells intensely unpleasant to most people (sweaty, urinous) while a genetic minority finds it pleasant or cannot detect it at all. This specific anosmia affects roughly 25–50% of the population. Androstenol smells muskier and more sandalwood-like. Neither would be described as 'attractive' in a fragrance evaluation context.
The Full Story
The concept of pheromones was formalised in 1959 by Peter Karlson and Martin Lüscher, who defined them as substances secreted externally that trigger specific reactions in other members of the same species. The first identified pheromone was bombykol, the sex attractant of the silkworm moth Bombyx mori. In insects, pheromone systems are unambiguous: a single molecule can attract a mate from kilometres away.
The human case is far more complex. Humans produce volatile steroid derivatives — androstenone, androstenol, androstadienone, estratetraenol — that are structurally analogous to pheromones in other mammals. These are found in sweat, particularly apocrine sweat from the axillae (armpits). Some studies have reported subtle effects: shifts in mood, changes in cortisol levels, altered perception of attractiveness. But the effects are small, inconsistent across studies, and highly context-dependent.
A critical anatomical issue is the vomeronasal organ (VNO), or Jacobson's organ. In many mammals, the VNO detects pheromones via a dedicated neural pathway separate from the main olfactory system. Humans possess a vestigial VNO, but its sensory neurons appear non-functional in adults, and its neural connections to the brain are absent or degenerate. This does not rule out pheromone detection via the main olfactory epithelium, but it removes the most obvious detection mechanism.
The commercial 'pheromone perfume' market, valued at several hundred million dollars globally, typically adds synthetic androstenone, androstenol, or proprietary blends to conventional fragrances. Marketing claims range from 'increased attractiveness' to 'instant chemistry.' Controlled, double-blind studies have not consistently supported these claims. A 2016 meta-analysis in the Royal Society's Proceedings B concluded that evidence for human pheromonal communication remains insufficient.
This does not mean fragrance has no effect on attraction. It does — through psychological association, cultural conditioning, and genuine olfactory preference. These effects are well-documented and real. They are simply not pheromonal in the strict biological sense.
Did You Know?
Did you know?
Bombykol, the silkworm moth pheromone identified in 1959, required processing 500,000 female moths to isolate 12 milligrams of the pure compound. A single molecule of bombykol is enough to trigger a response in a male moth's antenna. No human chemical signal has ever demonstrated comparable specificity or potency.
Extraction & Chemistry
In Perfumery
Pheromones have no established functional role in fine perfumery. Certain animalic materials — musk, civet, castoreum, ambergris — were historically described as 'pheromone-like' due to their biological origins, but their effect in fragrance is aesthetic and associative, not biochemical. The marketing of pheromone-containing perfumes persists as a consumer category despite the absence of strong scientific support.
